Software:
Systems and Application Software
Identify and briefly describe the functions of the two basic kinds of software
Outline the role of the operating system and identify the features of several popular operating systems
Discuss how application software can support personal, workgroup, and enterprise business objectives
Identify three basic approaches to developing application software and discuss the pros and cons of each
Outline the overall evolution and importance of programming languages and clearly differentiate among the generations of programming languages
Identify several key software issues and trends that have an impact on organizations and individuals
2. 2
Principles and Learning Objectives
1. Identify and briefly describe the functions of the two basic kinds of
software
2. Outline the role of the operating system and identify the features
of several popular operating systems
3. Discuss how application software can support personal,
workgroup, and enterprise business objectives
4. Identify three basic approaches to developing application software
and discuss the pros and cons of each
5. Outline the overall evolution and importance of programming
languages and clearly differentiate among the generations of
programming languages
6. Identify several key software issues and trends that have an
impact on organizations and individuals
3. 3
Why Learn About Software?
• Software is indispensable for any computer system
• Systems software needed for input, calculations,
and output
• Application software aids in productivity
• Personal tasks using software
– Income tax preparation
– Keeping a budget
– Internet research
– Games
4. 4
An Overview of Software
• Computer programs: sequences of
instructions for the computer
• Documentation: describes program functions
• Software – system software and application
software
5. 5
Systems Software
• Systems software: coordinates the activities and
functions of hardware and programs
• Computer system platform: combination of a
hardware configuration and systems software
6. 6
Application Software
• Application software: helps users solve particular
problems
• In most cases, application software resides on the
computer’s hard disk
• Application software can also be stored on CDs,
DVDs, and flash or keychain storage devices
7. 7
Supporting Individual, Group, and
Organizational Goals
• Organisation – people, workgroup, enterprise –
supported with software and IS
• Organisation needs to classify the software and IS
uses to increase productivity – need to identify the
scope of problems and opportunities
• Sphere of influence: the scope of problems and
opportunities addressed by a particular
organisation
• For most companies, the spheres of influence are
personal, workgroup, and enterprise
8. 8
Supporting Individual, Group, and
Organizational Goals (continued)
Table : Software Supporting Individuals, Workgroups, and Enterprises
9. 9
Installing and Removing Software for
PCs
• Before you can use software, it must be installed
on a computer
• Software for personal computers typically comes
on CDs or is downloaded from the Web
• Most operating systems have an add/remove
program feature for removing software
– Does not work with all software
– Does not always remove all elements of the software
10. 10
Systems Software
• Systems software
– Controls operations of computer hardware
– Supports application programs’ problem-solving
capabilities
• Types of systems software
– Operating systems
– Utility programs
– Middleware
11. 11
Operating Systems
• Operating system (OS): set of programs that
controls the computer hardware and acts as an
interface with application programs
• Kernel: ties all components of the OS together and
regulates other programs
12. 12
Operating Systems (continued)
• Various combinations of OSs, computers, and
users
– Single computer with a single user
– Single computer with multiple users
– Multiple computers
– Special-purpose computers
13. 13
Operating Systems (continued)
• Activities performed by the operating system
– Perform common computer hardware functions
– Provide a user interface and input/output
management
– Provide a degree of hardware independence
– Manage system memory
– Manage processing tasks
– Provide networking capability
– Control access to system resources
– Manage files
15. 15
Operating Systems (continued)
• OS acts as an intermediary between application
and hardware
• OS converts basic request into a set of details
instruction that the hardware requires
• Common hardware functions (e.g.)
– Get input from keyboard or some other input device
– Retrieve data from disks
– Store data on disks
– Display information on a monitor or printer
16. 16
Operating Systems Functions
1. User interface and input/output management
– User interface: allows individuals to access and
command the computer system
– Command-based user interface: requires that text
commands be given to the computer to perform
basic activities
– Graphical user interface (GUI): uses icons and
menus displayed on screen to send commands to
the computer system
17. 17
Operating Systems Functions
(continued)
2. Hardware independence
– Application program interface (API): allows
applications to make use of the operating system
3. Memory management
– Control how memory is accessed and maximize
available memory and storage
19. 19
4. Processing tasks
– Multitasking: more than one program can run at the
same time
– Time-sharing: allows more than one person to use
a computer system at the same time
– Scalability: ability of the computer to handle an
increasing number of concurrent users smoothly
5. Networking capability
– Features and capabilities of the OS that aid users in
connecting to a computer network
Operating Systems (continued)
20. 20
Operating Systems (continued)
6. Access to system resources and security
– Protection against unauthorized access
– Logins and passwords
7. File management
– Ensures that files in secondary storage are available
when needed and that they are protected from
access by unauthorized users
22. 22
Current Operating Systems
(continued)
• Microsoft PC operating systems
– PC-DOS and MS-DOS: early, command-driven OSs
– Windows XP: greatly improved stability and security
over previous versions of Windows
– Windows XP N: for European market
– Windows XP Professional X64: for computers with
newer 64-bit capabilities
– Windows XP Media Center Edition: incorporates
additional multimedia features
– Vista: latest version of Windows
23. 23
Current Operating Systems
(continued)
• Apple operating systems
– Often provide cutting edge tools in graphics and
music not available from Microsoft
– Mac OS X
• Jaguar (OS X.2)
• Panther (OS X.3)
• Tiger (OS X.4): support for 64-bit computing,
Dashboard, Spotlight, etc.
24. 24
Current Operating Systems
(continued)
• Linux
– Developed by Linus Torvalds in 1991
– Open-source product
– Only the kernel of an OS
– Several distributions available with
capabilities/applications that form a complete OS
• Examples: Red Hat Linux, Caldera OpenLinux
27. 27
Operating Systems for Small
Computers, Embedded Computers,
and Special-Purpose Devices
• Palm OS
• Windows Embedded
• Windows Mobile
28. 28
Utility Programs
• Help to perform maintenance or correct problems
with a computer sistem
• Common types of utility programs:
– Hardware utilities
– Virus-detection and recovery utilities
– File-compression utilities
– Spam and pop-up blocker utilities
29. 29
Utility Programs (continued)
• Network and Internet utilities
• Server and mainframe utilities
• Other utilities
– Manages and protects corporate documents
– Helps people with visual disabilities use the Internet
– Monitors employees
– Searches for files and documents
30. 30
Middleware
• Middleware: software that allows different systems
to communicate and exchange data
• Middleware can also be used as an interface
between the Internet and older legacy systems
• e.g. ?
31. 31
Application Software
• Primary function is to apply the power of the
computer to give individuals, workgroups, and the
entire enterprise the ability to solve problems and
perform specific tasks
• Application programs interact with systems
software; systems software then directs computer
hardware to perform the necessary tasks
32. 32
Overview of Application Software
• Proprietary software: one-of-a-kind program for a
specific application, usually developed and owned
by a single company
• Off-the-shelf software: existing software program
that is purchased
34. 34
Overview of Application Software
(continued)
Table: A Comparison of Proprietary and Off-the-Shelf Software
35. 35
Overview of Application Software
(continued)
Table: A Comparison of Proprietary and Off-the-Shelf Software
(continued)
36. 36
Personal Application Software
• Serves the needs of an individual user
• Includes personal productivity software
– Enables users to improve their personal
effectiveness
39. 39
Personal Application Software
(continued)
• Software suite: collection of single application
programs packaged in a bundle
– Microsoft Office: most popular general-purpose
software suite
– Other general-purpose software suites: Corel’s
WordPerfect Office, Lotus SmartSuite, Sun
Microsystems’s StarOffice
• Integrated application packages: offer a range of
capabilities for less money than software suites
– Example: Microsoft Works
41. 41
Workgroup Application Software
• Workgroup application software: support
teamwork, whether people are in the same location
or dispersed around the world
• Groupware: software that helps groups of people
work together more efficiently and effectively
43. 43
Enterprise Application Software
• Software that benefits an entire organization
• Enterprise resource planning (ERP) software:
set of integrated programs that manage a
company’s vital business operations for an entire
multisite, global organization
45. 45
Application Software for Information,
Decision Support, and Specialized
Purposes
• Specialized application software for information,
decision support, and other purposes is available in
every industry
• Examples
– Genetic researchers use software to visualize and
analyze the human genome
– Music executives use decision support software to
help pick the next hit
– Decision support software is used to increase the
cure rate for cancer
46. 46
Programming Languages
• Sets of keywords, symbols, and a system of rules
for constructing statements by which humans can
communicate instructions to be executed by a
computer
• Different languages have different characteristics
• Syntax: a set of rules associated with a
programming language
47. 47
The Evolution of Programming
Languages
Table : The Evolution of Programming Languages
48. 48
The Evolution of Programming
Languages (continued)
• Visual, object-oriented, and artificial intelligence
languages are easier for nonprogrammers to use
than older generation languages
• Visual languages use a graphical or visual interface
for program development
• Object-oriented programming languages are based
on objects
• Compiler: a special software program that
converts programmer’s source code into machine-
language instructions consisting of binary digits
49. 49
The Evolution of Programming
Languages (continued)
Figure : Reusable Code in Object-Oriented Programming
50. 50
The Evolution of Programming
Languages (continued)
Figure : How a Compiler Works
51. 51
Software Issues and Trends
• Because software is such an important part of
today’s computer systems, software issues have
received increased attention
• Major software issues and trends discussed in the
text
– Software bugs, copyright, software licensing, open-
source software, shareware and public domain
software, multiorganizational software development,
software upgrades, and global software support
52. 52
Software Bugs
• Software bug: defect in a computer program that
keeps it from performing as it is designed to
perform
• Tips for reducing impact of software bugs
– Register all software so that you can receive bug
alerts, fixes, and patches
– Check the manual or read-me files for work-arounds
– Access support area of the manufacturer’s Web site
for patches
– Install the latest software updates
53. 53
Copyrights and Licenses
• Most software products are protected by law using
copyright or licensing provisions
– In some cases, you are given unlimited use of
software on one or two computers
– In other cases, you pay for your usage—if you use
the software more, you pay more
• Some software now requires that you register or
activate it before it can be fully used
54. 54
Open-Source Software
• Open-source software: software freely available
to anyone in a form that can be easily modified
• Some widely used open-source software
packages: Linux OS, Free BSD, Apache,
Sendmail, Perl
• Open-source software is often more reliable and
secure than commercial software
• Open-source systems can contain hidden costs,
particularly for user support or solving problems
with the software
56. 56
Shareware, Freeware, and Public
Domain Software
• Shareware and freeware: software that is very
inexpensive or free, but whose source code cannot
be modified
• Public domain software: shareware and freeware
that is in the public domain
57. 57
Software Upgrades
• Software companies revise their programs and sell
new versions periodically
• Revised software may or may not offer any major
additional capabilities
• Revised software can contain bugs or errors
• Software upgrades usually cost much less than the
original purchase price
58. 58
Global Software Support
• Vendors face the challenge of providing adequate
support for their software customers in all locations
of the world
• Trend of outsourcing global support to one or more
third-party distributors
59. 59
Summary
• Computer programs: sequences of instructions for
the computer
• Systems software: coordinates the activities of
hardware and programs
• Applications software: helps users solve particular
problems
• Operating system (OS): set of computer programs
that controls the computer hardware and acts as an
interface with application programs
60. 60
Summary (continued)
• Graphical user interface (GUI): user interface that
uses icons and menus displayed on screen to send
commands to the computer system
• Time-sharing: allows more than one person to use
a computer system at the same time
• Proprietary software: one-of-a-kind program for a
specific application, usually developed and owned
by a single company
• Off-the-shelf software: existing software program
that is purchased
61. 61
Summary (continued)
• Enterprise resource planning (ERP) software:
manages a company’s vital business operations for
an entire multisite, global organization
• Programming languages: allow humans to
communicate instructions to be executed by a
computer
• Most software products are protected by law using
copyright or licensing provisions
• Open-source software is freely available to anyone
in a form that can be easily modified